1. Field of the Invention
The present invention generally relates to a communication device enabling data transmission and reception without contacting, and more specifically, a reader/writer performing communications without contacting an IC (Integrated Circuit) tag.
2. Description of the Related Art
In recent years, the RFID (Radio Frequency Identification) system has become popular, which system is characterized by reading and writing data in an IC card containing an IC chip therein without contacting the IC card. In such an RFID system, an IC card (or called IC tag) and an RFID reader/writer (or called only reader/writer) are used. The RFID reader/writer reads and writes data in the IC card.
Since such an RFID reader/writer performing data transmission and reception with the IC card is configured to perform data communication by utilizing an antenna thereof, the RFID reader/writer is characterized by enabling data transmission and reception without contacting. Accordingly, as for an antenna structure, various forms are suggested. (For example, see the Patent Documents 1 and 2)
[Patent Document 1]
Japanese Patent Publication No. 2004-118440
[Patent Document 2]
Japanese Patent Publication No. 2004-166175
However, when establishing an RFID system, it is necessary to connect an antenna. Accordingly, it is difficult to reduce the size and thickness of the RFID system. For example, as for a communication device such as an RFID reader/writer, it is necessary to connect an antenna. Thus, it is difficult to reduce a size of the reader/writer. Further, it is necessary to provide wirings for connecting the antenna. As a result, the structure of the reader/writer becomes complicated.